The Pi4 is HOT. And if you want an attractive, passively-cooled way to keep it happy, look at this heat-sink sandwich.
The Raspberry Pi 4 can definitely run hot. And if you want to cool it in style in a totally-passive manner, check this out.
This is a custom-machined aluminium 2-sided heat-sink that is practically a full-metal enclosure. It bolts your Raspberry Pi 4 between two slabs of anodised aluminum providing 10~15°C of cooling. There are slots and ports for all the necessary Pi accessories, but you may need to use some sort of pin booster to sufficiently clear the heatsink metal. Remember, it is metal, and can short pins out on any HATs you may want to mount on it.
Be sure to use only one of the included sticky thermal pads on the center CPU.